Sunflower Sentinel. Lawrence, Kansas: Hercules Powder Company, June 25, 1942

Sunflower Sentinel. Lawrence, Kansas: Hercules Powder Company, June 25, 1942, Volume: Gilbert E250. Robert L. Gilbert First Issues collection, Gilbert. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/527652 Accessed December 28, 2025.